Ovens heretofore developed have been known to have ventilation systems for exhausting gases from the oven liner and for diluting those gases with air before discharging them into the area surrounding the oven. Such ovens have generally employed forced air ventilation systems and thermal current ventilation systems. A forced air system uses a mechanical fan for circulating air through the oven, whereas a thermal current ventilation system utilizes air flow caused by oven heat to direct air through the desired passages.
Forced air ventilation systems have been found generally effective, but the cost of the fan represents an additional expense. Furthermore, if for any reason the fan becomes inoperable, the oven may heat its surroundings to a dangerously high temperature. For these reasons, a passive ventilation system using naturally forming thermal currents is often preferrable to the forced air system.
Prior passive ventilation systems normally produce a smaller volume of air flow than the forced air systems. The reduced air flow in some ovens has resulted in inadequate cooling characteristics and unsatisfactory dilution of oven liner gases before discharge. A need has thus arisen for a passive ventilation system having improved cooling characteristics which provides a mechanism for adequately diluting and cooling oven liner gases.
Smoke eliminating panels have also been previously used in conjunction with broiler heating elements in order to reduce the amount of smoke vented from an oven. However, such smoke eliminating panels and their associated heating elements have not only not provided desirable uniform radiant heat distribution inside an oven, but have not been integrated in the design of an oven venting system in order to provide improved cooling and ventilation.